What Is a Servo Cylinder?
Servo cylinders are electric actuators that convert the rotational motion of a motor into linear motion using a ball screw. They allow for precise control over time, position, and load, offering advantages such as lower defect rates, improved yields, and simplified inspection processes over hydraulic cylinders. Choosing a compatible servo controller is crucial for various applications.
Hybrid production equipment combining servo cylinders with servo motors has been introduced to enhance manufacturing efficiency.
Uses of Servo Cylinders
Servo cylinders are primarily used in industrial machinery, such as press-fit mechanisms for gears and pulleys. They enable high-precision positioning with rapid response motors, often requiring a servo controller for operation, which may increase design and implementation time.
Principle of Servo Cylinders
Through a servo controller, servo cylinders can be precisely controlled by setting parameters such as time, position, and load. There are two main control methods: load control and position control. An example of load control involves moving at a specific speed until a certain load is reached, holding at a load for a set time, and then returning to the original position at a defined speed.
Structure of Servo Cylinders
The servo cylinder consists of a ball screw, linear guide, and servo motor, with variations in size but a consistent basic structure. The ball screw transforms the motor’s rotational motion into linear motion with high accuracy. The linear guide supports this motion, ensuring smooth operation. Servo motors, equipped with encoders, allow for precise rotation and linear distance control.
1. Ball Screw
Ball screws offer high transmission and positioning accuracy, connecting to the servo motor via timing pulleys and belts, or directly through a coupling.
2. Linear Guide
Linear guides support and guide the ball screw’s motion, compensating for its intolerance to non-linear forces.
3. Servo Motors
Servo motors, integrated with encoders, facilitate accurate control of rotation and, consequently, the linear motion produced by the ball screw.
Types of Servo Cylinder
Servo cylinders come in two main types: rod and slider.
1. Rod Type
Rod types, suitable for push movements, require more space and may need a linear guide or be of a guided type to handle radial loads efficiently.
2. Slider Type
Slider types operate along a linear guide’s rail, allowing direct mounting of the moving object. Selection involves ensuring the slider’s moment load and payload capacities are not exceeded by the attached object’s weight and operating conditions.
Consideration of the payload’s variation between vertical and horizontal orientations is also crucial.